There is described in U.S. Pat. No. 4,696,386, a diverter turn assembly that can be configured to divert articles from a path of a conveying system to another path, to merge articles arriving on two paths into one path or to function as a corner section. Such a turn assembly includes an array of wheels or rollers mounted on a frame. The wheels or rollers are arranged so continuously moving belt(s) on which the articles travel pass freely through the array. The wheels or rollers of the turn assembly are normally disposed beneath the surface of the belts and raised pneumatically when required to change the direction of the moving product or article. The rollers for the corner sections are typically arranged so they always present a contact surface slightly higher than the belts. The orientation and shape of the wheels is adjusted to match the function to be formed (e.g., diversion, merger, turning at a corner). For example, for a merge unit the rollers are orientated across the belt line.
Although such a device can readily divert and turn articles, it is limited to a single change in direction for diversion or merging (i.e., "T" conveying system configurations). This increases the size and number of sections required to divert and/or merge articles. Although this device also is well suited for diverting and merging articles in conveying system, it has limited capability to sort articles in particular when performing high speed sorting operations.
The universal controller for this device, as described in co-pending U.S. application Ser. No. 08/752,587, is well suited to control the performance of the diverting and merging functions by the device. However, it also has limited capability to perform sorting operations, in particular high speed sorting operations. As also described therein, this controller uses a local area communication scheme to control the operation of systems or devices connected to the controllers and thereby decentralize these control functions.
Additionally, other existing control systems and control methodologies, particularly those for conveying systems, employ some form of centralized control over multiple device controllers. For example, two device controllers are hard wired interconnected to a programmable logic controller (PLC) or a plurality of PLCs, each being hardwired to device controllers, are hard wired connected to another central PLC. To effect a change in the operation of one device in response to changing conditions for another device, the PLC identifies the changing conditions and sends a signal to the other controller.
Such other systems are difficult to modify in the field by the user (i.e, not user friendly). System modifications typically involves re-configuring or replacing each control component (i.e, controller and PLC) in the system. As such, these types of systems are expensive and time consuming and have little flexibility for field modification.
Conveying and sorting systems traditionally have been custom designed with centralized controls and complex customized software for tracking articles or goods in movement in the system. Modifications to such systems entail adjustments to the centralized controls, revision to the customized software and the de-bugging required following such changes to assure proper system operation. Further, because the software and controls for each system is customized for each system, it is difficult to combine the control logic with the mechanical of the conveying system.
As such, there is a need for an apparatus that is configurable to selectively and automatically perform uni-directional and/or bi-directional sorting and diverting of articles. More particularly an apparatus that can perform high speed uni-directional and/or bi-directional diversion and sorting. There also is a need for such a controller to communicate with each other on a local area basis. Additionally, there is a need for a controller which is particularly configured to support the high speed sorting and/or diverting capability of the sorting/diverting apparatus. Such controllers also should not require hard wired interconnections but use communication protocols and equipment as a means for communicating between controllers. There also is a need for a sorting system that uses one or a plurality of such apparatuses. There also is a need for a conveying system that uses such an apparatus in conjunction with other conveying sections using local area based communication schemes and controllers so as to increase flexibility while maintaining control over the flow of goods or articles through the system without centralized control and customized software. Moreover, there is a need for conveying and sorting systems that are modularized in design and operation so customized engineering is not required.